The mainstream of air conditioners for house use is those adopting the heat pump method and coming in the separate type divided into an outdoor unit and an indoor unit. In this connection, PTL 1 discloses an air conditioner which automatically stops the heating operation when the outdoor temperature becomes extremely low, for example, −15° C. or lower.
In the conventional air conditioner described in PTL 1, when the outdoor temperature has come out of a device-usable temperature range, the compressor and the outdoor fan are stopped while the indoor fan is operated as a circulator. As a result, damage to the compressor and the outdoor heat exchanger can be prevented, and moreover it is designed to achieve improvement in comfortableness by virtue of circulation of the indoor air.